1. Field of the Invention
The present invention is concerned with a vaccine for Erysipelothrix Rhusiopathiae (E. rhusiopathiae) and a vaccine for Haemophilus Parasuis (H. parasuis). More particularly, the present invention is concerned with a vaccine for conferring effective immunity against E. rhusiopathiae and H. parasuis and methods of making the same. Still more particularly, the present invention is concerned with a vaccine which can be administered in a single dose and provide a duration of immunity (DOI) of a desired length. Even more particularly, the present invention is concerned with a single dose vaccine which provides a DOI equivalent to the average life span of an animal receiving the vaccine.
2. Description of the Prior Art
E. rhusiopathiae is a gram-positive bacteria that is pathogenic to over 50 species of vertebrate and invertebrate animals including swine, sheep, lambs, cattle, ducks, turkeys, and humans. H. parasuis is a gram-negative bacteria that is pathogenic to many animals, most notably swine. Vaccines against E. rhusiopathiae and H. parasuis are typically separate and consist of multiple doses given over the life span of an animal in order to confer effective immunity against E. rhusiopathiae and H. parasuis. There currently exists a vaccine against H. parasuis which can be administered in a single dose but a separate vaccination against E. rhusiopathiae must still be given. As is well known in the art, problems with vaccines that require more than one dose include the time and expense needed to track which animals have received first and/or second or subsequent doses, to track when the first dose was given, to do the actual vaccination, the increased size of the animals between first and subsequent doses, the increased risk of injury to the animal and to the person giving the subsequent doses of vaccine, and the expense associated with providing multiple doses.
What is needed in the art is a 1-dose regimen which confers effective immunity to an animal receiving the vaccination wherein the vaccine provides an extended DOI longer than is presently available through vaccines. What is further needed is a vaccine against E. rhusiopathiae that is administered in a single dose and provides a DOI of about six months. What is still further needed is a vaccine against E. rhusiopathiae and H. parasuis that provides a DOI of about six months after just a single dose of the vaccine.